First, I would like to commend you for your courage in asking this question. All too often, we have come to believe that the man of God is infallible and beyond examination.
As I read your question I was reminded off Paul's beef with Peter, who acted in a similar manner, forgetting what God had done for the Gentiles and reverting to the sectarian mentality he once had.
Galatians 3 tells us the story:
11 But when Peter came to Antioch, I opposed him in public, because he was clearly wrong. 12 Before some men who had been sent by James arrived there, Peter had been eating with the Gentile brothers and sisters. But after these men arrived, he drew back and would not eat with the Gentiles, because he was afraid of those who were in favor of circumcising them. 13 The other Jewish brothers and sisters also started acting like cowards along with Peter; and even Barnabas was swept along by their cowardly action. 14 When I saw that they were not walking a straight path in line with the truth of the gospel, I said to Peter in front of them all, “You are a Jew, yet you have been living like a Gentile, not like a Jew. How, then, can you try to force Gentiles to live like Jews?
There are some parallels to be drawn with this passage and your situation.
The most troublesome part of scenario that you described is that at one time your pastor sat with all the saints at various tables and apparently is contradicting what he espouses, and once practiced.
Sometimes, like all of us, pastors fall into the trap of pride that Peter fell prey to. Furthermore, we cannot discount that this might be a reason for his 'sudden' change. It may very well be he has lost his compass and needs to be reminded of what he has taught and once practiced.
Having been raised in Pentecost, I have observed a widening gap between the ministry and laity in
some of our circles. Each church and pastor is unique and different, but I see a trend. A levitical mindset that promotes nepotism and favoritism has gripped us, thus creating a clique of sorts.
However, there may be mitigating factors. As a pastor's kid, I have observed that at certain times various personalities may have the pastor's ear.
Perhaps the person(s) in charge of organizing these events has convinced him this is the best way to do things. Sometimes, in our efforts to be so formal and professional, things become impersonalized.
Or perhaps there is an innocent explanation for the change.
With that said, what should you do? Should you call your pastor out in public like Paul did.
NO WAY!!! Paul had authority to do so.
So what to do, then?
Approach this situation, like our Master would, and as he instructed.
Matthew 18:15 say " Moreover if thy brother shall trespass against thee, go and tell him his fault
between thee and him alone: if he shall hear thee, thou hast gained thy brother."
I am sure that if you approached your pastor, in private, with humility, reverence and candor you might be surprised with the outcome. Maybe he will give a better insight for the 'change'. Perhaps he will provide you with a perspective you did not see. Or perhaps you will serve as a wake up call for him.
Most of all, Fonix, continue to be subject to your pastor and pray for him daily.